GHSA-4mhg-xv73-xq2x

Source

https://github.com/advisories/GHSA-4mhg-xv73-xq2x

Import Source

https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2024/12/GHSA-4mhg-xv73-xq2x/GHSA-4mhg-xv73-xq2x.json

JSON Data

https://api.test.osv.dev/v1/vulns/GHSA-4mhg-xv73-xq2x

Aliases

Published

2024-12-03T18:39:12Z

Modified

2026-06-06T00:45:25Z

Severity

7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
8.7 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N CVSS Calculator

Summary

Synapse denial of service through media disk space consumption

Details

Impact

Synapse versions before 1.106 are vulnerable to a disk fill attack, where an unauthenticated adversary can induce Synapse to download and cache large amounts of remote media. The default rate limit strategy is insufficient to mitigate this. This can lead to a denial of service, ranging from further media uploads/downloads failing to completely unavailability of the Synapse process, depending on how Synapse was deployed.

Patches

Synapse 1.106 introduces a new "leaky bucket" rate limit on remote media downloads to reduce the amount of data a user can request at a time. This does not fully address the issue, but does limit an unauthenticated user's ability to request large amounts of data to be cached.

Workarounds

Synapse deployments can currently decrease the maximum file size allowed, as well as increase request rate limits. However, this does not as effectively address the issue as a dedicated rate limit on remote media downloads.

Server operators may also wish to consider putting media on a dedicated disk or volume, reducing the impact of a disk fill condition.

References

https://en.wikipedia.org/wiki/Leaky_bucket#As_a_meter

For more information

If you have any questions or comments about this advisory, please email us at security at element.io.

Database specific

{
    "cwe_ids": [
        "CWE-770"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2024-12-03T18:39:12Z",
    "nvd_published_at": "2024-12-03T17:15:10Z",
    "severity": "HIGH"
}

References

Affected packages

PyPI / matrix-synapse

Package

Name: matrix-synapse; View open source insights on deps.dev
Purl: pkg:pypi/matrix-synapse

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0 Unknown introduced version / All previous versions are affected

Fixed

1.106

Affected versions

0.*

0.33.5

0.33.5.1

0.33.6rc1

0.33.6

0.33.7rc1

0.33.7rc2

0.33.7

0.33.8rc2

0.33.8

0.33.9

0.34.0rc1

0.34.0rc2

0.34.0

0.34.0.1

0.34.1.1

0.99.0rc1

0.99.0rc2

0.99.0rc3

0.99.0rc4

0.99.0

0.99.1rc1

0.99.1rc2

0.99.1

0.99.1.1

0.99.2rc1

0.99.2

0.99.3rc1

0.99.3

0.99.3.1

0.99.3.2

0.99.4rc1

0.99.4

0.99.5rc1

0.99.5

0.99.5.1

0.99.5.2

1.*

1.0.0rc1

1.0.0rc2

1.0.0rc3

1.0.0

1.1.0rc1

1.1.0rc2

1.1.0

1.2.0rc1

1.2.0rc2

1.2.0

1.2.1

1.3.0rc1

1.3.0

1.3.1

1.4.0rc1

1.4.0rc2

1.4.0

1.4.1rc1

1.4.1

1.5.0rc1

1.5.0rc2

1.5.0

1.5.1

1.6.0rc1

1.6.0rc2

1.6.0

1.6.1

1.7.0rc1

1.7.0rc2

1.7.0

1.7.1

1.7.2

1.7.3

1.8.0rc1

1.8.0

1.9.0.dev1

1.9.0.dev2

1.9.0rc1

1.9.0

1.9.1

1.10.0rc1

1.10.0rc2

1.10.0rc3

1.10.0rc5

1.10.0

1.10.1

1.11.0rc1

1.11.0

1.11.1

1.12.0rc1

1.12.0

1.12.1rc1

1.12.1

1.12.2

1.12.3

1.12.4rc1

1.12.4

1.13.0rc1

1.13.0rc2

1.13.0rc3

1.13.0

1.14.0rc1

1.14.0rc2

1.14.0

1.15.0rc1

1.15.0

1.15.1

1.15.2

1.16.0rc1

1.16.0rc2

1.16.0

1.16.1

1.17.0rc1

1.17.0

1.18.0rc1

1.18.0rc2

1.18.0

1.19.0rc1

1.19.0

1.19.1rc1

1.19.1

1.19.2

1.19.3

1.20.0rc1

1.20.0rc2

1.20.0rc3

1.20.0rc4

1.20.0rc5

1.20.0

1.20.1

1.21.0rc1

1.21.0rc2

1.21.0rc3

1.21.0

1.21.1

1.21.2

1.22.0rc1

1.22.0rc2

1.22.0

1.22.1

1.23.0rc1

1.23.0

1.23.1

1.24.0rc1

1.24.0rc2

1.24.0

1.25.0rc1

1.25.0

1.26.0rc1

1.26.0rc2

1.26.0

1.27.0rc1

1.27.0rc2

1.27.0

1.28.0rc1

1.28.0

1.29.0rc1

1.29.0

1.30.0rc1

1.30.0

1.30.1

1.31.0rc1

1.31.0

1.32.0rc1

1.32.0

1.32.1

1.32.2

1.33.0rc1

1.33.0rc2

1.33.0

1.33.1

1.33.2

1.34.0rc1

1.34.0

1.35.0rc1

1.35.0rc2

1.35.0rc3

1.35.0

1.35.1

1.36.0rc1

1.36.0rc2

1.36.0

1.37.0rc1

1.37.0

1.37.1rc1

1.37.1

1.38.0rc1

1.38.0rc2

1.38.0rc3

1.38.0

1.38.1

1.39.0rc1

1.39.0rc2

1.39.0rc3

1.39.0

1.40.0rc1

1.40.0rc2

1.40.0rc3

1.40.0

1.41.0rc1

1.41.0

1.41.1

1.42.0rc1

1.42.0rc2

1.42.0

1.43.0rc1

1.43.0rc2

1.43.0

1.44.0rc1

1.44.0rc2

1.44.0rc3

1.44.0

1.45.0rc1

1.45.0rc2

1.45.0

1.45.1

1.46.0rc1

1.46.0

1.47.0rc1

1.47.0rc2

1.47.0rc3

1.47.0

1.47.1

1.48.0rc1

1.48.0

1.49.0rc1

1.49.0

1.49.2

1.50.0rc1

1.50.0rc2

1.50.0

1.50.1

1.50.2

1.51.0rc1

1.51.0rc2

1.51.0

1.52.0rc1

1.52.0

1.53.0rc1

1.53.0

1.54.0rc1

1.54.0

1.55.0rc1

1.55.0

1.55.1

1.55.2

1.56.0rc1

1.56.0

1.57.0rc1

1.57.0

1.57.1

1.58.0rc2

1.58.0

1.58.1

1.59.0rc1

1.59.0rc2

1.59.0

1.59.1

1.60.0rc1

1.60.0rc2

1.60.0

1.61.0rc1

1.61.0

1.61.1

1.62.0rc1

1.62.0rc2

1.62.0rc3

1.62.0

1.63.0rc1

1.63.0

1.63.1

1.64.0rc1

1.64.0rc2

1.64.0

1.65.0rc1

1.65.0rc2

1.65.0

1.66.0rc1

1.66.0rc2

1.66.0

1.67.0rc1

1.67.0

1.68.0rc1

1.68.0rc2

1.68.0

1.69.0rc1

1.69.0rc2

1.69.0rc4

1.69.0

1.70.0rc1

1.70.0rc2

1.70.0

1.70.1

1.71.0rc1

1.71.0rc2

1.71.0

1.72.0rc1

1.72.0

1.73.0rc2

1.73.0

1.74.0rc1

1.74.0

1.75.0rc1

1.75.0rc2

1.75.0

1.76.0rc1

1.76.0rc2

1.76.0

1.77.0rc1

1.77.0rc2

1.77.0

1.78.0rc1

1.78.0

1.79.0rc1

1.79.0rc2

1.79.0

1.80.0rc1

1.80.0rc2

1.80.0

1.81.0rc1

1.81.0rc2

1.81.0

1.82.0rc1

1.82.0

1.83.0rc1

1.83.0

1.84.0rc1

1.84.0

1.84.1

1.85.0rc1

1.85.0rc2

1.85.0

1.85.1

1.85.2

1.86.0rc2

1.86.0

1.87.0rc1

1.87.0

1.88.0rc1

1.88.0

1.89.0rc1

1.89.0

1.90.0rc1

1.90.0

1.91.0rc1

1.91.0

1.91.1

1.91.2

1.92.0rc1

1.92.1

1.92.2

1.92.3

1.93.0rc1

1.93.0

1.94.0rc1

1.94.0

1.95.0rc1

1.95.0

1.95.1

1.96.0rc1

1.96.1

1.97.0rc1

1.97.0

1.98.0rc1

1.98.0

1.99.0rc1

1.99.0

1.100.0rc2

1.100.0rc3

1.100.0

1.101.0rc1

1.101.0

1.102.0rc1

1.102.0

1.103.0rc1

1.103.0

1.104.0rc1

1.104.0

1.105.0rc1

1.105.0

1.105.1

1.106.0rc1

Database specific

source

"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2024/12/GHSA-4mhg-xv73-xq2x/GHSA-4mhg-xv73-xq2x.json"